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diff --git a/dom/html/HTMLImageElement.cpp b/dom/html/HTMLImageElement.cpp
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/HTMLImageElement.h"
+#include "mozilla/PresShell.h"
+#include "mozilla/dom/BindContext.h"
+#include "mozilla/dom/BindingUtils.h"
+#include "mozilla/dom/HTMLImageElementBinding.h"
+#include "mozilla/dom/NameSpaceConstants.h"
+#include "nsGenericHTMLElement.h"
+#include "nsGkAtoms.h"
+#include "nsStyleConsts.h"
+#include "nsPresContext.h"
+#include "nsMappedAttributes.h"
+#include "nsSize.h"
+#include "mozilla/dom/Document.h"
+#include "nsImageFrame.h"
+#include "nsIScriptContext.h"
+#include "nsContentUtils.h"
+#include "nsContainerFrame.h"
+#include "nsNodeInfoManager.h"
+#include "mozilla/MouseEvents.h"
+#include "nsContentPolicyUtils.h"
+#include "nsFocusManager.h"
+#include "mozilla/dom/DOMIntersectionObserver.h"
+#include "mozilla/dom/HTMLFormElement.h"
+#include "mozilla/dom/MutationEventBinding.h"
+#include "mozilla/dom/UserActivation.h"
+#include "nsAttrValueOrString.h"
+#include "imgLoader.h"
+#include "Image.h"
+
+// Responsive images!
+#include "mozilla/dom/HTMLSourceElement.h"
+#include "mozilla/dom/ResponsiveImageSelector.h"
+
+#include "imgINotificationObserver.h"
+#include "imgRequestProxy.h"
+
+#include "mozilla/CycleCollectedJSContext.h"
+
+#include "mozilla/EventDispatcher.h"
+#include "mozilla/MappedDeclarations.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/RestyleManager.h"
+
+#include "nsLayoutUtils.h"
+
+using namespace mozilla::net;
+using mozilla::Maybe;
+
+NS_IMPL_NS_NEW_HTML_ELEMENT(Image)
+
+#ifdef DEBUG
+// Is aSubject a previous sibling of aNode.
+static bool IsPreviousSibling(const nsINode* aSubject, const nsINode* aNode) {
+ if (aSubject == aNode) {
+ return false;
+ }
+
+ nsINode* parent = aSubject->GetParentNode();
+ if (parent && parent == aNode->GetParentNode()) {
+ const Maybe<uint32_t> indexOfSubject = parent->ComputeIndexOf(aSubject);
+ const Maybe<uint32_t> indexOfNode = parent->ComputeIndexOf(aNode);
+ if (MOZ_LIKELY(indexOfSubject.isSome() && indexOfNode.isSome())) {
+ return *indexOfSubject < *indexOfNode;
+ }
+ // XXX Keep the odd traditional behavior for now.
+ return indexOfSubject.isNothing() && indexOfNode.isSome();
+ }
+
+ return false;
+}
+#endif
+
+namespace mozilla::dom {
+
+// Calls LoadSelectedImage on host element unless it has been superseded or
+// canceled -- this is the synchronous section of "update the image data".
+// https://html.spec.whatwg.org/multipage/embedded-content.html#update-the-image-data
+class ImageLoadTask final : public MicroTaskRunnable {
+ public:
+ ImageLoadTask(HTMLImageElement* aElement, bool aAlwaysLoad,
+ bool aUseUrgentStartForChannel)
+ : MicroTaskRunnable(),
+ mElement(aElement),
+ mAlwaysLoad(aAlwaysLoad),
+ mUseUrgentStartForChannel(aUseUrgentStartForChannel) {
+ mDocument = aElement->OwnerDoc();
+ mDocument->BlockOnload();
+ }
+
+ void Run(AutoSlowOperation& aAso) override {
+ if (mElement->mPendingImageLoadTask == this) {
+ mElement->mPendingImageLoadTask = nullptr;
+ mElement->mUseUrgentStartForChannel = mUseUrgentStartForChannel;
+ mElement->LoadSelectedImage(true, true, mAlwaysLoad);
+ }
+ mDocument->UnblockOnload(false);
+ }
+
+ bool Suppressed() override {
+ nsIGlobalObject* global = mElement->GetOwnerGlobal();
+ return global && global->IsInSyncOperation();
+ }
+
+ bool AlwaysLoad() const { return mAlwaysLoad; }
+
+ private:
+ ~ImageLoadTask() = default;
+ RefPtr<HTMLImageElement> mElement;
+ nsCOMPtr<Document> mDocument;
+ bool mAlwaysLoad;
+
+ // True if we want to set nsIClassOfService::UrgentStart to the channel to
+ // get the response ASAP for better user responsiveness.
+ bool mUseUrgentStartForChannel;
+};
+
+HTMLImageElement::HTMLImageElement(
+ already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
+ : nsGenericHTMLElement(std::move(aNodeInfo)),
+ mForm(nullptr),
+ mInDocResponsiveContent(false),
+ mCurrentDensity(1.0) {
+ // We start out broken
+ AddStatesSilently(ElementState::BROKEN);
+}
+
+HTMLImageElement::~HTMLImageElement() { nsImageLoadingContent::Destroy(); }
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(HTMLImageElement, nsGenericHTMLElement,
+ mResponsiveSelector)
+
+NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED(HTMLImageElement,
+ nsGenericHTMLElement,
+ nsIImageLoadingContent,
+ imgINotificationObserver)
+
+NS_IMPL_ELEMENT_CLONE(HTMLImageElement)
+
+bool HTMLImageElement::IsInteractiveHTMLContent() const {
+ return HasAttr(kNameSpaceID_None, nsGkAtoms::usemap) ||
+ nsGenericHTMLElement::IsInteractiveHTMLContent();
+}
+
+void HTMLImageElement::AsyncEventRunning(AsyncEventDispatcher* aEvent) {
+ nsImageLoadingContent::AsyncEventRunning(aEvent);
+}
+
+void HTMLImageElement::GetCurrentSrc(nsAString& aValue) {
+ nsCOMPtr<nsIURI> currentURI;
+ GetCurrentURI(getter_AddRefs(currentURI));
+ if (currentURI) {
+ nsAutoCString spec;
+ currentURI->GetSpec(spec);
+ CopyUTF8toUTF16(spec, aValue);
+ } else {
+ SetDOMStringToNull(aValue);
+ }
+}
+
+bool HTMLImageElement::Draggable() const {
+ // images may be dragged unless the draggable attribute is false
+ return !AttrValueIs(kNameSpaceID_None, nsGkAtoms::draggable,
+ nsGkAtoms::_false, eIgnoreCase);
+}
+
+bool HTMLImageElement::Complete() {
+ // It is still not clear what value should img.complete return in various
+ // cases, see https://github.com/whatwg/html/issues/4884
+
+ if (!HasAttr(nsGkAtoms::srcset) && !HasNonEmptyAttr(nsGkAtoms::src)) {
+ return true;
+ }
+
+ if (!mCurrentRequest || mPendingRequest) {
+ return false;
+ }
+
+ uint32_t status;
+ mCurrentRequest->GetImageStatus(&status);
+ return (status &
+ (imgIRequest::STATUS_LOAD_COMPLETE | imgIRequest::STATUS_ERROR)) != 0;
+}
+
+CSSIntPoint HTMLImageElement::GetXY() {
+ nsIFrame* frame = GetPrimaryFrame(FlushType::Layout);
+ if (!frame) {
+ return CSSIntPoint(0, 0);
+ }
+ return CSSIntPoint::FromAppUnitsRounded(
+ frame->GetOffsetTo(frame->PresShell()->GetRootFrame()));
+}
+
+int32_t HTMLImageElement::X() { return GetXY().x; }
+
+int32_t HTMLImageElement::Y() { return GetXY().y; }
+
+void HTMLImageElement::GetDecoding(nsAString& aValue) {
+ GetEnumAttr(nsGkAtoms::decoding, kDecodingTableDefault->tag, aValue);
+}
+
+// https://whatpr.org/html/3752/urls-and-fetching.html#lazy-loading-attributes
+static const nsAttrValue::EnumTable kLoadingTable[] = {
+ {"eager", HTMLImageElement::Loading::Eager},
+ {"lazy", HTMLImageElement::Loading::Lazy},
+ {nullptr, 0}};
+
+void HTMLImageElement::GetLoading(nsAString& aValue) const {
+ GetEnumAttr(nsGkAtoms::loading, kLoadingTable[0].tag, aValue);
+}
+
+HTMLImageElement::Loading HTMLImageElement::LoadingState() const {
+ const nsAttrValue* val = mAttrs.GetAttr(nsGkAtoms::loading);
+ if (!val) {
+ return HTMLImageElement::Loading::Eager;
+ }
+ return static_cast<HTMLImageElement::Loading>(val->GetEnumValue());
+}
+
+already_AddRefed<Promise> HTMLImageElement::Decode(ErrorResult& aRv) {
+ return nsImageLoadingContent::QueueDecodeAsync(aRv);
+}
+
+bool HTMLImageElement::ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
+ const nsAString& aValue,
+ nsIPrincipal* aMaybeScriptedPrincipal,
+ nsAttrValue& aResult) {
+ if (aNamespaceID == kNameSpaceID_None) {
+ if (aAttribute == nsGkAtoms::align) {
+ return ParseAlignValue(aValue, aResult);
+ }
+ if (aAttribute == nsGkAtoms::crossorigin) {
+ ParseCORSValue(aValue, aResult);
+ return true;
+ }
+ if (aAttribute == nsGkAtoms::decoding) {
+ return aResult.ParseEnumValue(aValue, kDecodingTable,
+ /* aCaseSensitive = */ false,
+ kDecodingTableDefault);
+ }
+ if (aAttribute == nsGkAtoms::loading) {
+ return aResult.ParseEnumValue(aValue, kLoadingTable,
+ /* aCaseSensitive = */ false,
+ kLoadingTable);
+ }
+ if (ParseImageAttribute(aAttribute, aValue, aResult)) {
+ return true;
+ }
+ }
+
+ return nsGenericHTMLElement::ParseAttribute(aNamespaceID, aAttribute, aValue,
+ aMaybeScriptedPrincipal, aResult);
+}
+
+void HTMLImageElement::MapAttributesIntoRule(
+ const nsMappedAttributes* aAttributes, MappedDeclarations& aDecls) {
+ MapImageAlignAttributeInto(aAttributes, aDecls);
+ MapImageBorderAttributeInto(aAttributes, aDecls);
+ MapImageMarginAttributeInto(aAttributes, aDecls);
+ MapImageSizeAttributesInto(aAttributes, aDecls, MapAspectRatio::Yes);
+ MapCommonAttributesInto(aAttributes, aDecls);
+}
+
+nsChangeHint HTMLImageElement::GetAttributeChangeHint(const nsAtom* aAttribute,
+ int32_t aModType) const {
+ nsChangeHint retval =
+ nsGenericHTMLElement::GetAttributeChangeHint(aAttribute, aModType);
+ if (aAttribute == nsGkAtoms::usemap || aAttribute == nsGkAtoms::ismap) {
+ retval |= nsChangeHint_ReconstructFrame;
+ } else if (aAttribute == nsGkAtoms::alt) {
+ if (aModType == MutationEvent_Binding::ADDITION ||
+ aModType == MutationEvent_Binding::REMOVAL) {
+ retval |= nsChangeHint_ReconstructFrame;
+ }
+ }
+ return retval;
+}
+
+NS_IMETHODIMP_(bool)
+HTMLImageElement::IsAttributeMapped(const nsAtom* aAttribute) const {
+ static const MappedAttributeEntry* const map[] = {
+ sCommonAttributeMap, sImageMarginSizeAttributeMap,
+ sImageBorderAttributeMap, sImageAlignAttributeMap};
+
+ return FindAttributeDependence(aAttribute, map);
+}
+
+nsMapRuleToAttributesFunc HTMLImageElement::GetAttributeMappingFunction()
+ const {
+ return &MapAttributesIntoRule;
+}
+
+void HTMLImageElement::BeforeSetAttr(int32_t aNameSpaceID, nsAtom* aName,
+ const nsAttrValue* aValue, bool aNotify) {
+ if (aNameSpaceID == kNameSpaceID_None && mForm &&
+ (aName == nsGkAtoms::name || aName == nsGkAtoms::id)) {
+ // remove the image from the hashtable as needed
+ if (auto* old = GetParsedAttr(aName); old && !old->IsEmptyString()) {
+ mForm->RemoveImageElementFromTable(
+ this, nsDependentAtomString(old->GetAtomValue()));
+ }
+ }
+
+ return nsGenericHTMLElement::BeforeSetAttr(aNameSpaceID, aName, aValue,
+ aNotify);
+}
+
+void HTMLImageElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
+ const nsAttrValue* aValue,
+ const nsAttrValue* aOldValue,
+ nsIPrincipal* aMaybeScriptedPrincipal,
+ bool aNotify) {
+ if (aNameSpaceID != kNameSpaceID_None) {
+ return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
+ aOldValue,
+ aMaybeScriptedPrincipal, aNotify);
+ }
+
+ nsAttrValueOrString attrVal(aValue);
+
+ if (aValue) {
+ AfterMaybeChangeAttr(aNameSpaceID, aName, attrVal, aOldValue,
+ aMaybeScriptedPrincipal, aNotify);
+ }
+
+ if (mForm && (aName == nsGkAtoms::name || aName == nsGkAtoms::id) && aValue &&
+ !aValue->IsEmptyString()) {
+ // add the image to the hashtable as needed
+ MOZ_ASSERT(aValue->Type() == nsAttrValue::eAtom,
+ "Expected atom value for name/id");
+ mForm->AddImageElementToTable(
+ this, nsDependentAtomString(aValue->GetAtomValue()));
+ }
+
+ bool forceReload = false;
+
+ if (aName == nsGkAtoms::loading &&
+ !ImageState().HasState(ElementState::LOADING)) {
+ if (aValue && Loading(aValue->GetEnumValue()) == Loading::Lazy) {
+ SetLazyLoading();
+ } else if (aOldValue &&
+ Loading(aOldValue->GetEnumValue()) == Loading::Lazy) {
+ StopLazyLoading(StartLoading::Yes);
+ }
+ } else if (aName == nsGkAtoms::src && !aValue) {
+ // NOTE: regular src value changes are handled in AfterMaybeChangeAttr, so
+ // this only needs to handle unsetting the src attribute.
+ // Mark channel as urgent-start before load image if the image load is
+ // initaiated by a user interaction.
+ mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
+
+ // AfterMaybeChangeAttr handles setting src since it needs to catch
+ // img.src = img.src, so we only need to handle the unset case
+ if (InResponsiveMode()) {
+ if (mResponsiveSelector && mResponsiveSelector->Content() == this) {
+ mResponsiveSelector->SetDefaultSource(VoidString());
+ }
+ UpdateSourceSyncAndQueueImageTask(true);
+ } else {
+ // Bug 1076583 - We still behave synchronously in the non-responsive case
+ CancelImageRequests(aNotify);
+ }
+ } else if (aName == nsGkAtoms::srcset) {
+ // Mark channel as urgent-start before load image if the image load is
+ // initaiated by a user interaction.
+ mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
+
+ mSrcsetTriggeringPrincipal = aMaybeScriptedPrincipal;
+
+ PictureSourceSrcsetChanged(this, attrVal.String(), aNotify);
+ } else if (aName == nsGkAtoms::sizes) {
+ // Mark channel as urgent-start before load image if the image load is
+ // initiated by a user interaction.
+ mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
+
+ PictureSourceSizesChanged(this, attrVal.String(), aNotify);
+ } else if (aName == nsGkAtoms::decoding) {
+ // Request sync or async image decoding.
+ SetSyncDecodingHint(
+ aValue && static_cast<ImageDecodingType>(aValue->GetEnumValue()) ==
+ ImageDecodingType::Sync);
+ } else if (aName == nsGkAtoms::referrerpolicy) {
+ ReferrerPolicy referrerPolicy = GetReferrerPolicyAsEnum();
+ // FIXME(emilio): Why only when not in responsive mode? Also see below for
+ // aNotify.
+ forceReload = aNotify && !InResponsiveMode() &&
+ referrerPolicy != ReferrerPolicy::_empty &&
+ referrerPolicy != ReferrerPolicyFromAttr(aOldValue);
+ } else if (aName == nsGkAtoms::crossorigin) {
+ // FIXME(emilio): The aNotify bit seems a bit suspicious, but it is useful
+ // to avoid extra sync loads, specially in non-responsive mode. Ideally we
+ // can unify the responsive and non-responsive code paths (bug 1076583), and
+ // simplify this a bit.
+ forceReload = aNotify && GetCORSMode() != AttrValueToCORSMode(aOldValue);
+ }
+
+ if (forceReload) {
+ // Because we load image synchronously in non-responsive-mode, we need to do
+ // reload after the attribute has been set if the reload is triggered by
+ // cross origin / referrer policy changing.
+ //
+ // Mark channel as urgent-start before load image if the image load is
+ // initiated by a user interaction.
+ mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
+ if (InResponsiveMode()) {
+ // Per spec, full selection runs when this changes, even though
+ // it doesn't directly affect the source selection
+ UpdateSourceSyncAndQueueImageTask(true);
+ } else if (ShouldLoadImage()) {
+ // Bug 1076583 - We still use the older synchronous algorithm in
+ // non-responsive mode. Force a new load of the image with the
+ // new cross origin policy
+ ForceReload(aNotify, IgnoreErrors());
+ }
+ }
+
+ return nsGenericHTMLElement::AfterSetAttr(
+ aNameSpaceID, aName, aValue, aOldValue, aMaybeScriptedPrincipal, aNotify);
+}
+
+void HTMLImageElement::OnAttrSetButNotChanged(int32_t aNamespaceID,
+ nsAtom* aName,
+ const nsAttrValueOrString& aValue,
+ bool aNotify) {
+ AfterMaybeChangeAttr(aNamespaceID, aName, aValue, nullptr, nullptr, aNotify);
+ return nsGenericHTMLElement::OnAttrSetButNotChanged(aNamespaceID, aName,
+ aValue, aNotify);
+}
+
+void HTMLImageElement::AfterMaybeChangeAttr(
+ int32_t aNamespaceID, nsAtom* aName, const nsAttrValueOrString& aValue,
+ const nsAttrValue* aOldValue, nsIPrincipal* aMaybeScriptedPrincipal,
+ bool aNotify) {
+ if (aNamespaceID != kNameSpaceID_None || aName != nsGkAtoms::src) {
+ return;
+ }
+
+ // We need to force our image to reload. This must be done here, not in
+ // AfterSetAttr or BeforeSetAttr, because we want to do it even if the attr is
+ // being set to its existing value, which is normally optimized away as a
+ // no-op.
+ //
+ // If we are in responsive mode, we drop the forced reload behavior,
+ // but still trigger a image load task for img.src = img.src per
+ // spec.
+ //
+ // Both cases handle unsetting src in AfterSetAttr
+ // Mark channel as urgent-start before load image if the image load is
+ // initaiated by a user interaction.
+ mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
+
+ mSrcTriggeringPrincipal = nsContentUtils::GetAttrTriggeringPrincipal(
+ this, aValue.String(), aMaybeScriptedPrincipal);
+
+ if (InResponsiveMode()) {
+ if (mResponsiveSelector && mResponsiveSelector->Content() == this) {
+ mResponsiveSelector->SetDefaultSource(aValue.String(),
+ mSrcTriggeringPrincipal);
+ }
+ UpdateSourceSyncAndQueueImageTask(true);
+ } else if (aNotify && ShouldLoadImage()) {
+ // If aNotify is false, we are coming from the parser or some such place;
+ // we'll get bound after all the attributes have been set, so we'll do the
+ // sync image load from BindToTree. Skip the LoadImage call in that case.
+
+ // Note that this sync behavior is partially removed from the spec, bug
+ // 1076583
+
+ // A hack to get animations to reset. See bug 594771.
+ mNewRequestsWillNeedAnimationReset = true;
+
+ // Force image loading here, so that we'll try to load the image from
+ // network if it's set to be not cacheable.
+ // Potentially, false could be passed here rather than aNotify since
+ // UpdateState will be called by SetAttrAndNotify, but there are two
+ // obstacles to this: 1) LoadImage will end up calling
+ // UpdateState(aNotify), and we do not want it to call UpdateState(false)
+ // when aNotify is true, and 2) When this function is called by
+ // OnAttrSetButNotChanged, SetAttrAndNotify will not subsequently call
+ // UpdateState.
+ LoadSelectedImage(/* aForce = */ true, aNotify,
+ /* aAlwaysLoad = */ true);
+
+ mNewRequestsWillNeedAnimationReset = false;
+ }
+}
+
+void HTMLImageElement::GetEventTargetParent(EventChainPreVisitor& aVisitor) {
+ // We handle image element with attribute ismap in its corresponding frame
+ // element. Set mMultipleActionsPrevented here to prevent the click event
+ // trigger the behaviors in Element::PostHandleEventForLinks
+ WidgetMouseEvent* mouseEvent = aVisitor.mEvent->AsMouseEvent();
+ if (mouseEvent && mouseEvent->IsLeftClickEvent() && IsMap()) {
+ mouseEvent->mFlags.mMultipleActionsPrevented = true;
+ }
+ nsGenericHTMLElement::GetEventTargetParent(aVisitor);
+}
+
+nsINode* HTMLImageElement::GetScopeChainParent() const {
+ if (mForm) {
+ return mForm;
+ }
+ return nsGenericHTMLElement::GetScopeChainParent();
+}
+
+bool HTMLImageElement::IsHTMLFocusable(bool aWithMouse, bool* aIsFocusable,
+ int32_t* aTabIndex) {
+ int32_t tabIndex = TabIndex();
+
+ if (IsInComposedDoc() && FindImageMap()) {
+ if (aTabIndex) {
+ // Use tab index on individual map areas
+ *aTabIndex = (sTabFocusModel & eTabFocus_linksMask) ? 0 : -1;
+ }
+ // Image map is not focusable itself, but flag as tabbable
+ // so that image map areas get walked into.
+ *aIsFocusable = false;
+
+ return false;
+ }
+
+ if (aTabIndex) {
+ // Can be in tab order if tabindex >=0 and form controls are tabbable.
+ *aTabIndex = (sTabFocusModel & eTabFocus_formElementsMask) ? tabIndex : -1;
+ }
+
+ *aIsFocusable = IsFormControlDefaultFocusable(aWithMouse) &&
+ (tabIndex >= 0 || GetTabIndexAttrValue().isSome());
+
+ return false;
+}
+
+nsresult HTMLImageElement::BindToTree(BindContext& aContext, nsINode& aParent) {
+ nsresult rv = nsGenericHTMLElement::BindToTree(aContext, aParent);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ nsImageLoadingContent::BindToTree(aContext, aParent);
+
+ UpdateFormOwner();
+
+ if (HaveSrcsetOrInPicture()) {
+ if (IsInComposedDoc() && !mInDocResponsiveContent) {
+ aContext.OwnerDoc().AddResponsiveContent(this);
+ mInDocResponsiveContent = true;
+ }
+
+ // Mark channel as urgent-start before load image if the image load is
+ // initaiated by a user interaction.
+ mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
+
+ // Run selection algorithm when an img element is inserted into a document
+ // in order to react to changes in the environment. See note of
+ // https://html.spec.whatwg.org/multipage/embedded-content.html#img-environment-changes
+ //
+ // We also do this in PictureSourceAdded() if it is in <picture>, so here
+ // we only need to do if its parent is not <picture>, even if there is no
+ // <source>.
+ if (!IsInPicture()) {
+ UpdateSourceSyncAndQueueImageTask(false);
+ }
+ } else if (!InResponsiveMode() && HasAttr(nsGkAtoms::src)) {
+ // We skip loading when our attributes were set from parser land,
+ // so trigger a aForce=false load now to check if things changed.
+ // This isn't necessary for responsive mode, since creating the
+ // image load task is asynchronous we don't need to take special
+ // care to avoid doing so when being filled by the parser.
+
+ // Mark channel as urgent-start before load image if the image load is
+ // initaiated by a user interaction.
+ mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
+
+ // We still act synchronously for the non-responsive case (Bug
+ // 1076583), but still need to delay if it is unsafe to run
+ // script.
+
+ // If loading is temporarily disabled, don't even launch MaybeLoadImage.
+ // Otherwise MaybeLoadImage may run later when someone has reenabled
+ // loading.
+ if (LoadingEnabled() && ShouldLoadImage()) {
+ nsContentUtils::AddScriptRunner(
+ NewRunnableMethod<bool>("dom::HTMLImageElement::MaybeLoadImage", this,
+ &HTMLImageElement::MaybeLoadImage, false));
+ }
+ }
+
+ return rv;
+}
+
+void HTMLImageElement::UnbindFromTree(bool aNullParent) {
+ if (mForm) {
+ if (aNullParent || !FindAncestorForm(mForm)) {
+ ClearForm(true);
+ } else {
+ UnsetFlags(MAYBE_ORPHAN_FORM_ELEMENT);
+ }
+ }
+
+ if (mInDocResponsiveContent) {
+ OwnerDoc()->RemoveResponsiveContent(this);
+ mInDocResponsiveContent = false;
+ }
+
+ nsImageLoadingContent::UnbindFromTree(aNullParent);
+ nsGenericHTMLElement::UnbindFromTree(aNullParent);
+}
+
+void HTMLImageElement::UpdateFormOwner() {
+ if (!mForm) {
+ mForm = FindAncestorForm();
+ }
+
+ if (mForm && !HasFlag(ADDED_TO_FORM)) {
+ // Now we need to add ourselves to the form
+ nsAutoString nameVal, idVal;
+ GetAttr(kNameSpaceID_None, nsGkAtoms::name, nameVal);
+ GetAttr(kNameSpaceID_None, nsGkAtoms::id, idVal);
+
+ SetFlags(ADDED_TO_FORM);
+
+ mForm->AddImageElement(this);
+
+ if (!nameVal.IsEmpty()) {
+ mForm->AddImageElementToTable(this, nameVal);
+ }
+
+ if (!idVal.IsEmpty()) {
+ mForm->AddImageElementToTable(this, idVal);
+ }
+ }
+}
+
+void HTMLImageElement::MaybeLoadImage(bool aAlwaysForceLoad) {
+ // Our base URI may have changed, or we may have had responsive parameters
+ // change while not bound to the tree. However, at this moment, we should have
+ // updated the responsive source in other places, so we don't have to re-parse
+ // src/srcset here. Just need to LoadImage.
+
+ // Note, check LoadingEnabled() after LoadImage call.
+
+ LoadSelectedImage(aAlwaysForceLoad, /* aNotify */ true, aAlwaysForceLoad);
+
+ if (!LoadingEnabled()) {
+ CancelImageRequests(true);
+ }
+}
+
+ElementState HTMLImageElement::IntrinsicState() const {
+ return nsGenericHTMLElement::IntrinsicState() |
+ nsImageLoadingContent::ImageState();
+}
+
+void HTMLImageElement::NodeInfoChanged(Document* aOldDoc) {
+ nsGenericHTMLElement::NodeInfoChanged(aOldDoc);
+
+ // Unlike the LazyLoadImageObserver, the intersection observer
+ // for the viewport could contain the element even if
+ // it's not lazy-loading. For instance, the element has
+ // started to load, but haven't reached to the viewport.
+ // So here we always try to unobserve it.
+ if (auto* observer = aOldDoc->GetLazyLoadImageObserverViewport()) {
+ observer->Unobserve(*this);
+ }
+
+ if (mLazyLoading) {
+ aOldDoc->GetLazyLoadImageObserver()->Unobserve(*this);
+ mLazyLoading = false;
+ SetLazyLoading();
+ }
+
+ // Run selection algorithm synchronously when an img element's adopting steps
+ // are run, in order to react to changes in the environment, per spec,
+ // https://html.spec.whatwg.org/multipage/images.html#reacting-to-dom-mutations,
+ // and
+ // https://html.spec.whatwg.org/multipage/images.html#reacting-to-environment-changes.
+ if (InResponsiveMode()) {
+ UpdateResponsiveSource();
+ }
+
+ // Force reload image if adoption steps are run.
+ // If loading is temporarily disabled, don't even launch script runner.
+ // Otherwise script runner may run later when someone has reenabled loading.
+ StartLoadingIfNeeded();
+}
+
+// static
+already_AddRefed<HTMLImageElement> HTMLImageElement::Image(
+ const GlobalObject& aGlobal, const Optional<uint32_t>& aWidth,
+ const Optional<uint32_t>& aHeight, ErrorResult& aError) {
+ nsCOMPtr<nsPIDOMWindowInner> win = do_QueryInterface(aGlobal.GetAsSupports());
+ Document* doc;
+ if (!win || !(doc = win->GetExtantDoc())) {
+ aError.Throw(NS_ERROR_FAILURE);
+ return nullptr;
+ }
+
+ RefPtr<mozilla::dom::NodeInfo> nodeInfo = doc->NodeInfoManager()->GetNodeInfo(
+ nsGkAtoms::img, nullptr, kNameSpaceID_XHTML, ELEMENT_NODE);
+
+ auto* nim = nodeInfo->NodeInfoManager();
+ RefPtr<HTMLImageElement> img = new (nim) HTMLImageElement(nodeInfo.forget());
+
+ if (aWidth.WasPassed()) {
+ img->SetWidth(aWidth.Value(), aError);
+ if (aError.Failed()) {
+ return nullptr;
+ }
+
+ if (aHeight.WasPassed()) {
+ img->SetHeight(aHeight.Value(), aError);
+ if (aError.Failed()) {
+ return nullptr;
+ }
+ }
+ }
+
+ return img.forget();
+}
+
+uint32_t HTMLImageElement::Height() { return GetWidthHeightForImage().height; }
+
+uint32_t HTMLImageElement::Width() { return GetWidthHeightForImage().width; }
+
+nsIntSize HTMLImageElement::NaturalSize() {
+ if (!mCurrentRequest) {
+ return {};
+ }
+
+ nsCOMPtr<imgIContainer> image;
+ mCurrentRequest->GetImage(getter_AddRefs(image));
+ if (!image) {
+ return {};
+ }
+
+ nsIntSize size;
+ Unused << image->GetHeight(&size.height);
+ Unused << image->GetWidth(&size.width);
+
+ ImageResolution resolution = image->GetResolution();
+ // NOTE(emilio): What we implement here matches the image-set() spec, but it's
+ // unclear whether this is the right thing to do, see
+ // https://github.com/whatwg/html/pull/5574#issuecomment-826335244.
+ if (mResponsiveSelector) {
+ float density = mResponsiveSelector->GetSelectedImageDensity();
+ MOZ_ASSERT(density >= 0.0);
+ resolution.ScaleBy(density);
+ }
+
+ resolution.ApplyTo(size.width, size.height);
+ return size;
+}
+
+nsresult HTMLImageElement::CopyInnerTo(HTMLImageElement* aDest) {
+ nsresult rv = nsGenericHTMLElement::CopyInnerTo(aDest);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // In SetAttr (called from nsGenericHTMLElement::CopyInnerTo), aDest skipped
+ // doing the image load because we passed in false for aNotify. But we
+ // really do want it to do the load, so set it up to happen once the cloning
+ // reaches a stable state.
+ if (!aDest->InResponsiveMode() && aDest->HasAttr(nsGkAtoms::src) &&
+ aDest->ShouldLoadImage()) {
+ // Mark channel as urgent-start before load image if the image load is
+ // initaiated by a user interaction.
+ mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
+
+ nsContentUtils::AddScriptRunner(
+ NewRunnableMethod<bool>("dom::HTMLImageElement::MaybeLoadImage", aDest,
+ &HTMLImageElement::MaybeLoadImage, false));
+ }
+
+ return NS_OK;
+}
+
+CORSMode HTMLImageElement::GetCORSMode() {
+ return AttrValueToCORSMode(GetParsedAttr(nsGkAtoms::crossorigin));
+}
+
+JSObject* HTMLImageElement::WrapNode(JSContext* aCx,
+ JS::Handle<JSObject*> aGivenProto) {
+ return HTMLImageElement_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+#ifdef DEBUG
+HTMLFormElement* HTMLImageElement::GetForm() const { return mForm; }
+#endif
+
+void HTMLImageElement::SetForm(HTMLFormElement* aForm) {
+ MOZ_ASSERT(aForm, "Don't pass null here");
+ NS_ASSERTION(!mForm,
+ "We don't support switching from one non-null form to another.");
+
+ mForm = aForm;
+}
+
+void HTMLImageElement::ClearForm(bool aRemoveFromForm) {
+ NS_ASSERTION((mForm != nullptr) == HasFlag(ADDED_TO_FORM),
+ "Form control should have had flag set correctly");
+
+ if (!mForm) {
+ return;
+ }
+
+ if (aRemoveFromForm) {
+ nsAutoString nameVal, idVal;
+ GetAttr(nsGkAtoms::name, nameVal);
+ GetAttr(nsGkAtoms::id, idVal);
+
+ mForm->RemoveImageElement(this);
+
+ if (!nameVal.IsEmpty()) {
+ mForm->RemoveImageElementFromTable(this, nameVal);
+ }
+
+ if (!idVal.IsEmpty()) {
+ mForm->RemoveImageElementFromTable(this, idVal);
+ }
+ }
+
+ UnsetFlags(ADDED_TO_FORM);
+ mForm = nullptr;
+}
+
+void HTMLImageElement::UpdateSourceSyncAndQueueImageTask(
+ bool aAlwaysLoad, const HTMLSourceElement* aSkippedSource) {
+ // Per spec, when updating the image data or reacting to environment
+ // changes, we always run the full selection (including selecting the source
+ // element and the best fit image from srcset) even if it doesn't directly
+ // affect the source selection.
+ //
+ // However, in the spec of updating the image data, the selection of image
+ // source URL is in the asynchronous part (i.e. in a microtask), and so this
+ // doesn't guarantee that the image style is correct after we flush the style
+ // synchornously. So here we update the responsive source synchronously always
+ // to make sure the image source is always up-to-date after each DOM mutation.
+ // Spec issue: https://github.com/whatwg/html/issues/8207.
+ const bool changed = UpdateResponsiveSource(aSkippedSource);
+
+ // If loading is temporarily disabled, we don't want to queue tasks
+ // that may then run when loading is re-enabled.
+ if (!LoadingEnabled() || !ShouldLoadImage()) {
+ return;
+ }
+
+ // Ensure that we don't overwrite a previous load request that requires
+ // a complete load to occur.
+ bool alwaysLoad = aAlwaysLoad;
+ if (mPendingImageLoadTask) {
+ alwaysLoad = alwaysLoad || mPendingImageLoadTask->AlwaysLoad();
+ }
+
+ if (!changed && !alwaysLoad) {
+ return;
+ }
+
+ QueueImageLoadTask(alwaysLoad);
+}
+
+bool HTMLImageElement::HaveSrcsetOrInPicture() {
+ if (HasAttr(nsGkAtoms::srcset)) {
+ return true;
+ }
+
+ return IsInPicture();
+}
+
+bool HTMLImageElement::InResponsiveMode() {
+ // When we lose srcset or leave a <picture> element, the fallback to img.src
+ // will happen from the microtask, and we should behave responsively in the
+ // interim
+ return mResponsiveSelector || mPendingImageLoadTask ||
+ HaveSrcsetOrInPicture();
+}
+
+bool HTMLImageElement::SelectedSourceMatchesLast(nsIURI* aSelectedSource) {
+ // If there was no selected source previously, we don't want to short-circuit
+ // the load. Similarly for if there is no newly selected source.
+ if (!mLastSelectedSource || !aSelectedSource) {
+ return false;
+ }
+ bool equal = false;
+ return NS_SUCCEEDED(mLastSelectedSource->Equals(aSelectedSource, &equal)) &&
+ equal;
+}
+
+nsresult HTMLImageElement::LoadSelectedImage(bool aForce, bool aNotify,
+ bool aAlwaysLoad) {
+ // In responsive mode, we have to make sure we ran the full selection algrithm
+ // before loading the selected image.
+ // Use this assertion to catch any cases we missed.
+ MOZ_ASSERT(!UpdateResponsiveSource(),
+ "The image source should be the same because we update the "
+ "responsive source synchronously");
+
+ // The density is default to 1.0 for the src attribute case.
+ double currentDensity = mResponsiveSelector
+ ? mResponsiveSelector->GetSelectedImageDensity()
+ : 1.0;
+
+ nsCOMPtr<nsIURI> selectedSource;
+ nsCOMPtr<nsIPrincipal> triggeringPrincipal;
+ ImageLoadType type = eImageLoadType_Normal;
+ bool hasSrc = false;
+ if (mResponsiveSelector) {
+ selectedSource = mResponsiveSelector->GetSelectedImageURL();
+ triggeringPrincipal =
+ mResponsiveSelector->GetSelectedImageTriggeringPrincipal();
+ type = eImageLoadType_Imageset;
+ } else {
+ nsAutoString src;
+ hasSrc = GetAttr(nsGkAtoms::src, src);
+ if (hasSrc && !src.IsEmpty()) {
+ Document* doc = OwnerDoc();
+ StringToURI(src, doc, getter_AddRefs(selectedSource));
+ if (HaveSrcsetOrInPicture()) {
+ // If we have a srcset attribute or are in a <picture> element, we
+ // always use the Imageset load type, even if we parsed no valid
+ // responsive sources from either, per spec.
+ type = eImageLoadType_Imageset;
+ }
+ triggeringPrincipal = mSrcTriggeringPrincipal;
+ }
+ }
+
+ if (!aAlwaysLoad && SelectedSourceMatchesLast(selectedSource)) {
+ // Update state when only density may have changed (i.e., the source to load
+ // hasn't changed, and we don't do any request at all). We need (apart from
+ // updating our internal state) to tell the image frame because its
+ // intrinsic size may have changed.
+ //
+ // In the case we actually trigger a new load, that load will trigger a call
+ // to nsImageFrame::NotifyNewCurrentRequest, which takes care of that for
+ // us.
+ SetDensity(currentDensity);
+ return NS_OK;
+ }
+
+ // Before we actually defer the lazy-loading
+ if (mLazyLoading) {
+ if (!selectedSource ||
+ !nsContentUtils::IsImageAvailable(this, selectedSource,
+ triggeringPrincipal, GetCORSMode())) {
+ return NS_OK;
+ }
+ StopLazyLoading(StartLoading::No);
+ }
+
+ nsresult rv = NS_ERROR_FAILURE;
+
+ // src triggers an error event on invalid URI, unlike other loads.
+ if (selectedSource || hasSrc) {
+ rv = LoadImage(selectedSource, aForce, aNotify, type, triggeringPrincipal);
+ }
+
+ mLastSelectedSource = selectedSource;
+ mCurrentDensity = currentDensity;
+
+ if (NS_FAILED(rv)) {
+ CancelImageRequests(aNotify);
+ }
+ return rv;
+}
+
+void HTMLImageElement::PictureSourceSrcsetChanged(nsIContent* aSourceNode,
+ const nsAString& aNewValue,
+ bool aNotify) {
+ MOZ_ASSERT(aSourceNode == this || IsPreviousSibling(aSourceNode, this),
+ "Should not be getting notifications for non-previous-siblings");
+
+ nsIContent* currentSrc =
+ mResponsiveSelector ? mResponsiveSelector->Content() : nullptr;
+
+ if (aSourceNode == currentSrc) {
+ // We're currently using this node as our responsive selector
+ // source.
+ nsCOMPtr<nsIPrincipal> principal;
+ if (aSourceNode == this) {
+ principal = mSrcsetTriggeringPrincipal;
+ } else if (auto* source = HTMLSourceElement::FromNode(aSourceNode)) {
+ principal = source->GetSrcsetTriggeringPrincipal();
+ }
+ mResponsiveSelector->SetCandidatesFromSourceSet(aNewValue, principal);
+ }
+
+ if (!mInDocResponsiveContent && IsInComposedDoc()) {
+ OwnerDoc()->AddResponsiveContent(this);
+ mInDocResponsiveContent = true;
+ }
+
+ // This always triggers the image update steps per the spec, even if
+ // we are not using this source.
+ UpdateSourceSyncAndQueueImageTask(true);
+}
+
+void HTMLImageElement::PictureSourceSizesChanged(nsIContent* aSourceNode,
+ const nsAString& aNewValue,
+ bool aNotify) {
+ MOZ_ASSERT(aSourceNode == this || IsPreviousSibling(aSourceNode, this),
+ "Should not be getting notifications for non-previous-siblings");
+
+ nsIContent* currentSrc =
+ mResponsiveSelector ? mResponsiveSelector->Content() : nullptr;
+
+ if (aSourceNode == currentSrc) {
+ // We're currently using this node as our responsive selector
+ // source.
+ mResponsiveSelector->SetSizesFromDescriptor(aNewValue);
+ }
+
+ // This always triggers the image update steps per the spec, even if
+ // we are not using this source.
+ UpdateSourceSyncAndQueueImageTask(true);
+}
+
+void HTMLImageElement::PictureSourceMediaOrTypeChanged(nsIContent* aSourceNode,
+ bool aNotify) {
+ MOZ_ASSERT(IsPreviousSibling(aSourceNode, this),
+ "Should not be getting notifications for non-previous-siblings");
+
+ // This always triggers the image update steps per the spec, even if
+ // we are not switching to/from this source
+ UpdateSourceSyncAndQueueImageTask(true);
+}
+
+void HTMLImageElement::PictureSourceDimensionChanged(
+ HTMLSourceElement* aSourceNode, bool aNotify) {
+ MOZ_ASSERT(IsPreviousSibling(aSourceNode, this),
+ "Should not be getting notifications for non-previous-siblings");
+
+ // "width" and "height" affect the dimension of images, but they don't have
+ // impact on the selection of <source> elements. In other words,
+ // UpdateResponsiveSource doesn't change the source, so all we need to do is
+ // just request restyle.
+ if (mResponsiveSelector && mResponsiveSelector->Content() == aSourceNode) {
+ InvalidateAttributeMapping();
+ }
+}
+
+void HTMLImageElement::PictureSourceAdded(HTMLSourceElement* aSourceNode) {
+ MOZ_ASSERT(!aSourceNode || IsPreviousSibling(aSourceNode, this),
+ "Should not be getting notifications for non-previous-siblings");
+
+ UpdateSourceSyncAndQueueImageTask(true);
+}
+
+void HTMLImageElement::PictureSourceRemoved(HTMLSourceElement* aSourceNode) {
+ MOZ_ASSERT(!aSourceNode || IsPreviousSibling(aSourceNode, this),
+ "Should not be getting notifications for non-previous-siblings");
+
+ UpdateSourceSyncAndQueueImageTask(true, aSourceNode);
+}
+
+bool HTMLImageElement::UpdateResponsiveSource(
+ const HTMLSourceElement* aSkippedSource) {
+ bool hadSelector = !!mResponsiveSelector;
+
+ nsIContent* currentSource =
+ mResponsiveSelector ? mResponsiveSelector->Content() : nullptr;
+
+ // Walk source nodes previous to ourselves if IsInPicture().
+ nsINode* candidateSource =
+ IsInPicture() ? GetParentElement()->GetFirstChild() : this;
+
+ // Initialize this as nullptr so we don't have to nullify it when runing out
+ // of siblings without finding ourself, e.g. XBL magic.
+ RefPtr<ResponsiveImageSelector> newResponsiveSelector = nullptr;
+
+ for (; candidateSource; candidateSource = candidateSource->GetNextSibling()) {
+ if (aSkippedSource == candidateSource) {
+ continue;
+ }
+
+ if (candidateSource == currentSource) {
+ // found no better source before current, re-run selection on
+ // that and keep it if it's still usable.
+ bool changed = mResponsiveSelector->SelectImage(true);
+ if (mResponsiveSelector->NumCandidates()) {
+ bool isUsableCandidate = true;
+
+ // an otherwise-usable source element may still have a media query that
+ // may not match any more.
+ if (candidateSource->IsHTMLElement(nsGkAtoms::source) &&
+ !SourceElementMatches(candidateSource->AsElement())) {
+ isUsableCandidate = false;
+ }
+
+ if (isUsableCandidate) {
+ // We are still using the current source, but the selected image may
+ // be changed, so always set the density from the selected image.
+ SetDensity(mResponsiveSelector->GetSelectedImageDensity());
+ return changed;
+ }
+ }
+
+ // no longer valid
+ newResponsiveSelector = nullptr;
+ if (candidateSource == this) {
+ // No further possibilities
+ break;
+ }
+ } else if (candidateSource == this) {
+ // We are the last possible source
+ newResponsiveSelector =
+ TryCreateResponsiveSelector(candidateSource->AsElement());
+ break;
+ } else if (auto* source = HTMLSourceElement::FromNode(candidateSource)) {
+ if (RefPtr<ResponsiveImageSelector> selector =
+ TryCreateResponsiveSelector(source)) {
+ newResponsiveSelector = selector.forget();
+ // This led to a valid source, stop
+ break;
+ }
+ }
+ }
+
+ // If we reach this point, either:
+ // - there was no selector originally, and there is not one now
+ // - there was no selector originally, and there is one now
+ // - there was a selector, and there is a different one now
+ // - there was a selector, and there is not one now
+ SetResponsiveSelector(std::move(newResponsiveSelector));
+ return hadSelector || mResponsiveSelector;
+}
+
+/*static */
+bool HTMLImageElement::SupportedPictureSourceType(const nsAString& aType) {
+ nsAutoString type;
+ nsAutoString params;
+
+ nsContentUtils::SplitMimeType(aType, type, params);
+ if (type.IsEmpty()) {
+ return true;
+ }
+
+ return imgLoader::SupportImageWithMimeType(
+ NS_ConvertUTF16toUTF8(type), AcceptedMimeTypes::IMAGES_AND_DOCUMENTS);
+}
+
+bool HTMLImageElement::SourceElementMatches(Element* aSourceElement) {
+ MOZ_ASSERT(aSourceElement->IsHTMLElement(nsGkAtoms::source));
+
+ MOZ_ASSERT(IsInPicture());
+ MOZ_ASSERT(IsPreviousSibling(aSourceElement, this));
+
+ // Check media and type
+ auto* src = static_cast<HTMLSourceElement*>(aSourceElement);
+ if (!src->MatchesCurrentMedia()) {
+ return false;
+ }
+
+ nsAutoString type;
+ if (src->GetAttr(kNameSpaceID_None, nsGkAtoms::type, type) &&
+ !SupportedPictureSourceType(type)) {
+ return false;
+ }
+
+ return true;
+}
+
+already_AddRefed<ResponsiveImageSelector>
+HTMLImageElement::TryCreateResponsiveSelector(Element* aSourceElement) {
+ nsCOMPtr<nsIPrincipal> principal;
+
+ // Skip if this is not a <source> with matching media query
+ bool isSourceTag = aSourceElement->IsHTMLElement(nsGkAtoms::source);
+ if (isSourceTag) {
+ if (!SourceElementMatches(aSourceElement)) {
+ return nullptr;
+ }
+ auto* source = HTMLSourceElement::FromNode(aSourceElement);
+ principal = source->GetSrcsetTriggeringPrincipal();
+ } else if (aSourceElement->IsHTMLElement(nsGkAtoms::img)) {
+ // Otherwise this is the <img> tag itself
+ MOZ_ASSERT(aSourceElement == this);
+ principal = mSrcsetTriggeringPrincipal;
+ }
+
+ // Skip if has no srcset or an empty srcset
+ nsString srcset;
+ if (!aSourceElement->GetAttr(nsGkAtoms::srcset, srcset)) {
+ return nullptr;
+ }
+
+ if (srcset.IsEmpty()) {
+ return nullptr;
+ }
+
+ // Try to parse
+ RefPtr<ResponsiveImageSelector> sel =
+ new ResponsiveImageSelector(aSourceElement);
+ if (!sel->SetCandidatesFromSourceSet(srcset, principal)) {
+ // No possible candidates, don't need to bother parsing sizes
+ return nullptr;
+ }
+
+ nsAutoString sizes;
+ aSourceElement->GetAttr(nsGkAtoms::sizes, sizes);
+ sel->SetSizesFromDescriptor(sizes);
+
+ // If this is the <img> tag, also pull in src as the default source
+ if (!isSourceTag) {
+ MOZ_ASSERT(aSourceElement == this);
+ nsAutoString src;
+ if (GetAttr(nsGkAtoms::src, src) && !src.IsEmpty()) {
+ sel->SetDefaultSource(src, mSrcTriggeringPrincipal);
+ }
+ }
+
+ return sel.forget();
+}
+
+/* static */
+bool HTMLImageElement::SelectSourceForTagWithAttrs(
+ Document* aDocument, bool aIsSourceTag, const nsAString& aSrcAttr,
+ const nsAString& aSrcsetAttr, const nsAString& aSizesAttr,
+ const nsAString& aTypeAttr, const nsAString& aMediaAttr,
+ nsAString& aResult) {
+ MOZ_ASSERT(aIsSourceTag || (aTypeAttr.IsEmpty() && aMediaAttr.IsEmpty()),
+ "Passing type or media attrs makes no sense without aIsSourceTag");
+ MOZ_ASSERT(!aIsSourceTag || aSrcAttr.IsEmpty(),
+ "Passing aSrcAttr makes no sense with aIsSourceTag set");
+
+ if (aSrcsetAttr.IsEmpty()) {
+ if (!aIsSourceTag) {
+ // For an <img> with no srcset, we would always select the src attr.
+ aResult.Assign(aSrcAttr);
+ return true;
+ }
+ // Otherwise, a <source> without srcset is never selected
+ return false;
+ }
+
+ // Would not consider source tags with unsupported media or type
+ if (aIsSourceTag &&
+ ((!aMediaAttr.IsVoid() && !HTMLSourceElement::WouldMatchMediaForDocument(
+ aMediaAttr, aDocument)) ||
+ (!aTypeAttr.IsVoid() && !SupportedPictureSourceType(aTypeAttr)))) {
+ return false;
+ }
+
+ // Using srcset or picture <source>, build a responsive selector for this tag.
+ RefPtr<ResponsiveImageSelector> sel = new ResponsiveImageSelector(aDocument);
+
+ sel->SetCandidatesFromSourceSet(aSrcsetAttr);
+ if (!aSizesAttr.IsEmpty()) {
+ sel->SetSizesFromDescriptor(aSizesAttr);
+ }
+ if (!aIsSourceTag) {
+ sel->SetDefaultSource(aSrcAttr);
+ }
+
+ if (sel->GetSelectedImageURLSpec(aResult)) {
+ return true;
+ }
+
+ if (!aIsSourceTag) {
+ // <img> tag with no match would definitively load nothing.
+ aResult.Truncate();
+ return true;
+ }
+
+ // <source> tags with no match would leave source yet-undetermined.
+ return false;
+}
+
+void HTMLImageElement::DestroyContent() {
+ // Clear mPendingImageLoadTask to avoid running LoadSelectedImage() after
+ // getting destroyed.
+ mPendingImageLoadTask = nullptr;
+
+ mResponsiveSelector = nullptr;
+
+ nsImageLoadingContent::Destroy();
+ nsGenericHTMLElement::DestroyContent();
+}
+
+void HTMLImageElement::MediaFeatureValuesChanged() {
+ UpdateSourceSyncAndQueueImageTask(false);
+}
+
+bool HTMLImageElement::ShouldLoadImage() const {
+ return OwnerDoc()->ShouldLoadImages();
+}
+
+void HTMLImageElement::SetLazyLoading() {
+ if (mLazyLoading) {
+ return;
+ }
+
+ if (!StaticPrefs::dom_image_lazy_loading_enabled()) {
+ return;
+ }
+
+ // If scripting is disabled don't do lazy load.
+ // https://whatpr.org/html/3752/images.html#updating-the-image-data
+ //
+ // Same for printing.
+ Document* doc = OwnerDoc();
+ if (!doc->IsScriptEnabled() || doc->IsStaticDocument()) {
+ return;
+ }
+
+ doc->EnsureLazyLoadImageObserver().Observe(*this);
+ mLazyLoading = true;
+ UpdateImageState(true);
+}
+
+void HTMLImageElement::StartLoadingIfNeeded() {
+ if (!LoadingEnabled() || !ShouldLoadImage()) {
+ return;
+ }
+
+ // Use script runner for the case the adopt is from appendChild.
+ // Bug 1076583 - We still behave synchronously in the non-responsive case
+ nsContentUtils::AddScriptRunner(
+ InResponsiveMode()
+ ? NewRunnableMethod<bool>("dom::HTMLImageElement::QueueImageLoadTask",
+ this, &HTMLImageElement::QueueImageLoadTask,
+ true)
+ : NewRunnableMethod<bool>("dom::HTMLImageElement::MaybeLoadImage",
+ this, &HTMLImageElement::MaybeLoadImage,
+ true));
+}
+
+void HTMLImageElement::StopLazyLoading(StartLoading aStartLoading) {
+ if (!mLazyLoading) {
+ return;
+ }
+ mLazyLoading = false;
+ Document* doc = OwnerDoc();
+ if (auto* obs = doc->GetLazyLoadImageObserver()) {
+ obs->Unobserve(*this);
+ }
+
+ if (aStartLoading == StartLoading::Yes) {
+ StartLoadingIfNeeded();
+ }
+}
+
+const nsMappedAttributes* HTMLImageElement::GetMappedAttributesFromSource()
+ const {
+ if (!IsInPicture() || !mResponsiveSelector ||
+ !mResponsiveSelector->Content()) {
+ return nullptr;
+ }
+
+ const auto* source =
+ HTMLSourceElement::FromNode(mResponsiveSelector->Content());
+ if (!source) {
+ return nullptr;
+ }
+
+ MOZ_ASSERT(IsPreviousSibling(source, this),
+ "Incorrect or out-of-date source");
+ return source->GetAttributesMappedForImage();
+}
+
+void HTMLImageElement::InvalidateAttributeMapping() {
+ if (!IsInPicture()) {
+ return;
+ }
+
+ nsPresContext* presContext = nsContentUtils::GetContextForContent(this);
+ if (!presContext) {
+ return;
+ }
+
+ // Note: Unfortunately, we have to use RESTYLE_SELF, instead of using
+ // RESTYLE_STYLE_ATTRIBUTE or other ways, to avoid re-selector-match because
+ // we are using Gecko_GetExtraContentStyleDeclarations() to retrieve the
+ // extra declaration block from |this|'s width and height attributes, and
+ // other restyle hints seems not enough.
+ // FIXME: We may refine this together with the restyle for presentation
+ // attributes in RestyleManger::AttributeChagned()
+ presContext->RestyleManager()->PostRestyleEvent(
+ this, RestyleHint::RESTYLE_SELF, nsChangeHint(0));
+}
+
+void HTMLImageElement::SetResponsiveSelector(
+ RefPtr<ResponsiveImageSelector>&& aSource) {
+ if (mResponsiveSelector == aSource) {
+ return;
+ }
+
+ mResponsiveSelector = std::move(aSource);
+
+ // Invalidate the style if needed.
+ InvalidateAttributeMapping();
+
+ // Update density.
+ SetDensity(mResponsiveSelector
+ ? mResponsiveSelector->GetSelectedImageDensity()
+ : 1.0);
+}
+
+void HTMLImageElement::SetDensity(double aDensity) {
+ if (mCurrentDensity == aDensity) {
+ return;
+ }
+
+ mCurrentDensity = aDensity;
+
+ // Invalidate the reflow.
+ if (nsImageFrame* f = do_QueryFrame(GetPrimaryFrame())) {
+ f->ResponsiveContentDensityChanged();
+ }
+}
+
+void HTMLImageElement::QueueImageLoadTask(bool aAlwaysLoad) {
+ RefPtr<ImageLoadTask> task =
+ new ImageLoadTask(this, aAlwaysLoad, mUseUrgentStartForChannel);
+ // The task checks this to determine if it was the last
+ // queued event, and so earlier tasks are implicitly canceled.
+ mPendingImageLoadTask = task;
+ CycleCollectedJSContext::Get()->DispatchToMicroTask(task.forget());
+}
+
+} // namespace mozilla::dom
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-15 05:28:45 +0000